530 Notices of Books. [OCtober, 
beautiful blues then known, whether upon cottons, silks, or wool- 
lens. It was also essential in the manufacture of Prussian blue, 
which was then a leading pigment. Now, however, blues far 
finer and brighter than those produced with prussiate are dyed 
or printed with coal-tar compounds. On the other hand, artifi- 
cial ultramarine has greatly interfered with the use of Prussian 
blue. Hence the importance of prussiate of potash is declining, 
and there can be no longer the same interest felt in its manufac- 
ture. The whole field of technology—especially its chemical 
portion—is full of such revolutions. 
As an instance of an article nearly re-written, or at least 
enriched with a great amount of new and important matter, we 
may mention that on calico-printing. Many capital discoveries 
have been made, or at least introduced, into practical use since 
the appearance of the last edition. Accordingly, we find now 
full notice of the methods of applying the coal-tar colours, espe- 
cially the aniline-blacks—of the use of artificial alizarin and the 
improved extracts of madder, of the recent developments of pig- 
ment printing, and of the new indigo-vat of Schitzenberger 
and De Lalande—improvements which may be said to have 
created a perfectly new epoch in this wonderful art. The 
kindred department of dyeing is scarcely treated in as thorough- 
going and as practical a manner. In the article on sulphuric 
acid, we are glad to find that the recent important researches of 
Mr. H. A. Smith have not been passed unnoticed. He maintains 
that the best form of chambers should be rather long than high, 
being about 150 feet in length, 35 to 30 feet in width, and 1o to 
12 feet in height. 
The account of the artificial soda, or, as it is generally called, 
alkali-manufacture, includes brief notices of the new methods of 
Mr. Tilghman and of MM. Schleesing and Rolland, otherwise 
known as the ammonia-process. The arrangements for effecting 
the condensation of the muriatic gas, as required under the 
Alkali Act of 1863, are also described and illustrated with draw- 
ings of the towers at the celebrated works of Messrs. Alhusen. 
In short, it may generally be said that few recent improvements 
in any branch of manufactures have been entirely overlooked. - 
It would be, of course, easy to suggest additions which might 
have been made, and which would, doubtless, increase the value 
of the work. But the great point in a compilation of this kind 
is to include all that is really essential without rendering the » 
result too bulky, and consequently too costly. This end, we 
think, the editors have reached to a very satisfactory degree. 
The present edition is a book which no manufacturer, merchant, - 
miner, or technologist, should be without. 
